The meaning and origin of the expression: All systems go

All systems go

What's the meaning of the phrase 'All systems go'?

'All systems go' is what someone might say when all systems are functional and ready to proceed.

What's the origin of the phrase 'All systems go'?

'All systems go' sounds like a modern expression - something a test pilot or astronaut might say. If you are familiar with this website, this is the point where you might expect me to write that it is nothing of the kind and that it first appeared in Chaucer or the Bible or similar. In fact, popular etymology wins the day here and 'all systems go' did indeed originate as astronaut's jargon.

On 5th May 1961 Alan Shephard became the first American in space when the Freedom 7 spacecraft took off from Florida.

A transcript of Shephard's checking procedure went like this:

"Cabin pressure go."
"Fuel system go."
"Oxygen go."
"All systems go."

This was broadcast to an eagerly listening USA and, judging by the records of the number of uses of the expression in US newspapers, 'all systems go" entered the language there almost immediately.

It very soon became used more generally, in situations with nothing to do with spacecraft and not just in the USA. As soon as the following year it was being used in the UK, as in this report of a football match, in the Birmingham Daily Post, March 1962.

Then suddenly, just after half-time, it was "all systems go" for Spurs.